| /* @(#)w_gamma.c 5.1 93/09/24 */ |
| /* |
| * ==================================================== |
| * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
| * |
| * Developed at SunPro, a Sun Microsystems, Inc. business. |
| * Permission to use, copy, modify, and distribute this |
| * software is freely granted, provided that this notice |
| * is preserved. |
| * ==================================================== |
| */ |
| |
| #if defined(LIBM_SCCS) && !defined(lint) |
| static char rcsid[] = "$NetBSD: w_gamma.c,v 1.7 1995/11/20 22:06:43 jtc Exp $"; |
| #endif |
| |
| /* double gamma(double x) |
| * Return the logarithm of the Gamma function of x or the Gamma function of x, |
| * depending on the library mode. |
| */ |
| |
| #include <math.h> |
| #include "math_private.h" |
| |
| #ifdef __STDC__ |
| double __tgamma(double x) |
| #else |
| double __tgamma(x) |
| double x; |
| #endif |
| { |
| double y; |
| int local_signgam; |
| y = __ieee754_gamma_r(x,&local_signgam); |
| if (local_signgam < 0) y = -y; |
| #ifdef _IEEE_LIBM |
| return y; |
| #else |
| if(_LIB_VERSION == _IEEE_) return y; |
| |
| if(!__finite(y)&&__finite(x)) { |
| if (x == 0.0) |
| return __kernel_standard(x,x,50); /* tgamma pole */ |
| else if(__floor(x)==x&&x<0.0) |
| return __kernel_standard(x,x,41); /* tgamma domain */ |
| else |
| return __kernel_standard(x,x,40); /* tgamma overflow */ |
| } |
| return y; |
| #endif |
| } |
| weak_alias (__tgamma, tgamma) |
| #ifdef NO_LONG_DOUBLE |
| strong_alias (__tgamma, __tgammal) |
| weak_alias (__tgamma, tgammal) |
| #endif |
